Intercommunicating telephone.



No. 832,425. PATENTED OCT. 2, 1906.

L. SCHMIDT.

INTERGOMMUNICATING TELEPHONE.

APPLICATION FILED sEPT.1e,19o5.

5 SHEETS-SHEET 1.

SLEEPINBR. PANTRY Wdh/www4 I I Bry ATTORNEY No. 832,425. PATEN'IBI)00112, 1906.

L. SCHMIDT. v

INTERGOMMUNIGATING TELEPHONE.

APPLICATION FILED SEPT. 16, v1905. v

5 SHEETS-SHEET 2.

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...IIIIIIIMQHDNNIHINU I I .ey/2 ATTORNEY 150% L. SCHMIDT.

INTERCOMMUNICATING TELEPHONE. APPLIOATION FILED sBPT.1e,19o5.

PATENTED OCT. 2, 1906.

5 SHEETS-SHEET 3.

rus NoRms P ErERs ca., wAsHrNcTaN. u. r:v

PATENTED 00T. 2, 1906.

No- 882,425.O

L. SCHMIDT. INTERGOMMUNIGATING TELEPHONE'.

APPLIOTION FILED SEPT.16, 1905.

5 SHEETS-SHEET 4.

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Ms NaRRls PETERS cn., wAsmNafcN, n. c.

PATENTED OCT. 2, 1906.

, L. SCHMIDT.l

IIII'IRCOMMUNICA'FINGl TELEPHONE@ APPLICATION FILED SEPT. 16, 1905.

5 SHEETS-SHEET w1 11u@ J 7 M L f UNITED sTATns PATENT OFFIOE.

LAMBERT SCHMIDT, OF WEEHAWKEN, NEW JERSEY.

INTERCONINIUNICATING TELEPHONE.I l

Specification of .Letters Patent.

Patented Oct. 2, 1906.

Application led September 16,1905. Serial No. 278,698.

To LZZ whom, it may concern:

Be it known that I, LAMBERT SCHMIDT, a citizen of the United States ofAmerica, and a resident of Weehawken, county of I-Iudson, State of NewJersey, have invented certain new and useful Improvements inIntercommunicating Telephones, of which the following is a specication.

Tnis invention has reference to improvements in intercommunicatingtelephones.

It is the special object of this invention to provide a novelintercommunicating telephone which may be used as an interiorstation-telephone in both styles-the wall or desk telephone. Theinstrument comprises three distinct parts-namely, the station-indicatorwith switching device, the transmitter, and the receiver. Thestation-indicator and the switching device are combined in such a way asto form one self-contained part of the instrument, which isinterchangeable as a whole, whereas transmitter and receiver, togetherwith an element performing the function of a switch-hook, are combinedto constitute a second self-contained part of the instrument, which alsois interchangeable as a whole. vThese two parts are in such a relationto each other that the element performing the duty of a switch-hookretains the receiver in the second self-contained part and at the sametime actuates the switching device of the first self-contained part withstation-indicator.

My novel intercommunicating telephone is plain, very compact inconstruction,.and is cheaply manufactured. All single parts of theinstrument are interchangeable, and the combination of the single partsto two selfcontained main parts, which are interchangeable as a whole,makes it possible to use different casings or frames for the instrument,as is shown, for instance, in my Wall-telephone and my desk-telephone.

As station-indicator for my telephone I employ a circular dial on whichare printed the names of all the stations connected with the instrument.Selection .of the station with which it is desired to communicate ismade by means of a prominent radial hand pointing toward one of thestations printed on the dial. Thus the dial, with its hand, is in plainview of the person using the instrument and affords great facility formaking the proper'selection. The hand on the dial is set by means of acentrally-located knob, which at the same time performs the function ofa push-button. Owing to this construction only one push-button isrequired for indicating all stations, while the number of stations isonly limited by the size of the dial. The receiver is of the watchcasetype and is located directly in front of the transmitter, where it isheld by means of a suitable clamping device. A station may be called upwith the receiver on or off the instrument, and arrangements areprovided whereby the calling maybe effected either by means of a bell orthrough the receiver without the use of a bell. In order that twostations be electrically disconnected' when through talking with eachother, each receiver is placed again in front of the respectivetransmitter, whereby the talking-circuit is automatically opened and thecallingcircuit again restored.

' Another advantage of my telephone is derived from the Way theconnections to the wires of the house-cable are made. These wires aredirectly connected to binding-posts or contact-dowels without the use ofso-called intermediate cables or flexible wires. All the connectionsfrom the house-cables lead to a connection-board on the base of theinstrument, while the transmitter, receiver, and station-indicator, withswitching' device, are mounted and interconnected in the front part ofan independent casing, the latter having no connections whatever withthe base except when the instrument is closed.

The intercommunicating telephone is operated by a novel dial-switchwhich is actuated by the push-button. The button engages a switch-springof peculiar shape which makes Contact with one of a number ofcontact-dowels at a time. Said contactdowels have combined therewithbindingposts to which the single wires of the housecable are directlyconnected. This combination is of great advantage, as the intermediatecable or flexibles leading from this base to the instrument proper arethereby dispensed with. Thus the switch-spring of the dial-switch isused to form the electric connection with the desired station. or hand,also operated by the push-button, indicates the desired station directlyon the name-plate, and the pushing in of the button does not dislodgethe pointer. This .combination then renders it possible to dispense withthe extra push-buttons used in combination with dial-switches in formerconstructions. The button employed in A pointer- IOO forming part of thetalking-circuit.

system is first used to set the pointer over the name of the desiredstation on the namel plate or dial. Then it is pushed in in order tomake the call. The pushing in of the but- I ton depresses the curvedswitch-spring, the

pointed end of which always rests on one contact-dowel, and stillfurther pushing in will bring the inner end of the button in contactwith a spring forming part of the call, circuit.

When the finger is released from the push-button, the curvedswitch-spring forces the latter back far enough to interrupt thecall-circuit. At the same time it establishes an electrical connectionwith a latch The removal of the receivers 'from the instruments When theparty is through talking,

I-Iereby the talking-cirin the same position. In this way I dispensewith the so-called fly-back movement of; the switch employed informerconstructions. By virtue of the novel construction and shape of theswitch-spring I derive two dis-y tinct advantages, as follows: Thepointed end of thespring has a slight curvature or.

notch snugly iitting over the rounded head of the contact-dowels. vThepurpose of this notch is to lock the switch-spring in its position whenmaking electrical contact with a dowel. Thus I dispense with the pawlsand ratchets used for the same purpose in other,

constructions. vWhen the button is pressed in, not only is `the pressureof the switch-` springiupon the dowel greatly increased, but there isalso a slight rubbing action between these two elements, aording a verysubstantial electrical contact, which cannot be effected bythe meansgenerally employed in Aintercommunicating telephones.

The invention further consists in the details of construction andarrangements ofthe different parts.

The invention is illustrated intheaccompanying drawings, in which-Figure 1 represents in iront elevation an intercommunicatingwall-telephone which embodies my invention, having the receiver removed.Fig. '2 is a central longitudinal section of Fig. 1, showing thereceiver inserted in the transmitter. Fig. 3 illustrates in elevationthe telephone with certain rear parts removed. Fig. 4 shows same invelevation with certain yfront parts removed. Fig. 5 shows in :top planview the switch-spring. Figs. 46, 7, '8, and 9 are detail views of theswitch or vmechanical movement invarious positions. Fig. 10 representsin vertical section a desk-telephone with receiver in elevation insertedinto the transmitter. Fig. 11 shows a detail of :the switch ormechanical movement for the desk-telephone. Fig. 12 is an electricaldiagram comprising a bellcall, and Fig. 13 is another electrical diagramcomprising a receiver-call.

Similar characters of reference denote like parts in all the igures.

All parts of the telephone are mounted within a casing shown in Figs. 1,3, and 4. This casing consists of a base-plate a and a frame c with itstop 0,2. An opening a3 is provided in the 4frame, through which thehouse-cable passes. On the base-plate a fiber disk b is secured in itstop central portion. The fiber disk carries the combined binding-postsand contact-dowels c, which are circularly-arranged, as shown in Fig. 4,thus forming a multiple plug. Each of' these binding-posts andcontact-dowels represents a station. One, for instance, is connected tothe parlor instrument andthe other with the billiard-room instrument,&c. In the drawings ten of these contact-dowels are illustrated; buttheir number can be greater or smaller, according lto the number ofstations, and is only limited by the size of the dial used. The combinedbinding-posts and contact-dowels consist each of the dowel c', which isthreaded about half-way of its length, so that it may be secured in thefiber disk b and receive the binding-posts. A lock-nut c2 on the dowelrests on the :fiber disk. Then follows the binding-post c3, on whichagain rests a nut c4. The nut c4 'may be screwed up or down for thepurpose ofinserting andtightening the wires of the housecable. Theopposite and rounded ends or Vheads of thedowels form the contact-pointsfor the switch-spring.

Inside of the frame and neXt to the top there is secured a circularplate d, of insulating material, directly opposite the fiber-disk. Thisplate has va number of conical openings d', corresponding with thenumber of ycontact-dowels. The free end of each contact- IOC ITD

dowel passes kthrough and slightly extends' beyond one of theseopenings, which are also circularly arranged. A block e is alsosecuredto the plate d, carrying three contactsprings f, g, and h. Thecentral relatively short spring g forms part ofthe call-circuit.`

The longer springs f and h extend down to a mechanical movement, whichwill be described later. A contact plate yor latch i, having a circularconical opening'right before the central spring g, is pivotally mountedon the plate d. It formspart ofthe talkingcircuit. The latch has on `itslower end a cam t" and a spring i2, acting on the latch and tending topress same continuously againsta stop i3, so that the center of theconicalopening in the latch is somewhat lower thanthe center of thepushbutton locatedl directly I opposite it. v

On the top part a2 of the frame and in front of the supporting-plate dthere is mounted a dial or name-plate j, which has a circular centralopening coinciding with the opening in the supporting-plate d. Aswitchspring k, of peculiar shape, is held by the push-button betweenthe dial or name-plate and the supporting-plate. The switchspring isshown in top plan view in Fig. 5. The extension k on one side is the endresting on one of the contact-dowels. The central portion k2 extendsinwardly opposite from the extending portion 7c and reaches somewhatbeyond the center of the spring. Here the central portion has an oblongopening through which passes a certain part of the stem of thepush-button. The spring is curved, as shown in Fig. 2.

As mentioned before7 the end of the spring resting on the dowels has anotch k3, so that when the switch-spring is moved over the dowels by thepush-button it will positively snap in as soon as the notch drops overthe head of a dowel, thus indicating that the spring is properlylocated, and when 4the switch-spring is depressed by pushing in thebutton then a more perfect contact is effected than heretofore.

On the tcp of the frame and in front ofthe name-plate there is a glasscover l, having a central circular opening in which a bushing hZ isfitted. This opening coincides with the circular opening in thename-plate and' the circular opening in the supporting-plate.

The push-button m (see Fig. 2) passes through the openings in thevarious plates. Outside of the instrument it forms a knob m, from whichextends the stem m2. Near the switch-spring the stem is shaped so as tofit the oblong opening in said spring and to afford a shoulder retainingthe same.

of the same diameter as the preceding reduced part of the stem. Alongitudinal groove or key-seat m4 is cut into the part m2 of the stem.Between the glass cover and dial a pointer n is located. This pointer isattached to a sleeve n', which loosely surounds the stem of thepush-button. The

pointer extends through the body of thev slot o/ allows the bar alimited movement up.

Below. the switch-spring the stem is reduced in diameter, and furtherdown it terminates in a cone m3, this latter having a short elongationthat station.

or down, and a spring 04, attached to the bar on one end and fastened toa pin o5 in the plate at the other end, tends to pull the bar down andat the same time sidewise against a stop-pin 06. The top of the bar hasa cam 07, operating the similar cam i on the latch. The length of theslot is so selected as to allow the bar to be moved up and down farenough to engage the cam of the latch and to get clear of same. The pin03 engages either one of the springs f and h, mounted on the block e,according to the position of the baro. A block 08 is riveted to thelower end of the bar, as shown in Fig. 2. This block extends somewhatbeyond the bar.

Into the lower top part a2 of the casing there is mounted thetransmitter. The carbon button p usually employed is mounted in a metalframe, in front of which is clamped a diaphragm by means of a clamp-ringp2. To this clamp-ring is securely attached a bracket p3, forming one orthe lower part of the support for the receiver, while the other or upperpart of the sup ort is an angularlyshaped hook p4, pivota ly mounted onthe transmitter-frame p', extending through a suitable opening in thetop portion therein and terminating into a cap p5 of similar shape asthe bracket below. The receiver is thus clamped between the bracket andthe cap of the hook. The bar o rests upon the hook p4 by means of theblock 08, and the spring 04, acting on the bar, imparts to the hookenough ressure so that the latter is enabled to firmly liold thereceiverv in its place.

Assuming now that connection is desired with the music-room, forinstance, then the knob in front of the-'glass cover is turned arounduntil the pointer or hand which moves with the knob cornes to stay overMusic-room on the dial. Simultaneously the switch-spring 7c will bemoved along at the same rate, since the stem engages the oblongopeningvin the tongue or inner part k2 of the switch-spring. When thepointer stands above Music-room, the notched front end of theswitch-spring rests on the contact-dowel which makes connection with Nowthe knob is pushed in. Owing to the key-seat in the stem of thepush-button this latter is free to pass through the sleeve supportingthe hand without disturbing its position. While the push-button ismoving in, the curved switch-spring leaning against the shoulderv of thestem is de'- pressed and the pressure of its pointed end increased onthe contact-dowel. When passing further in, the cone m3 at the end ofthe stem will come in touch with the latch i, raise this latter untilthe cone is free to pass through the conical opening provided in thelatch, and then passing on until the extreme end of its small elongationfinally reaches the central spring g, whereby the call-circuit iscompleted. As soon as the coney has IOO IIO

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passed the opening in the latch the latter drops down again against itsstop i3. The knob after bein released will spring back by virtue of theorce of the `curved switchspring until the base oi the cone comes torest against the latch, whereby contact is established with thetalking-circuit.

While calling, the receiver may be on or off the instrument. Aftercalling, the receiver is removed Jfrom the bracket. Accordingly, thehook will drop and with it the bar o, carrying the pin o3. This pin, itwill be noticed, makes contact with either one oi the two long springs fand h, mounted in the block on the plate. Normally, when the receiver isin the bracket the pin o3 makes constant contact with the spring g,forming part oi the callcircuit, so that t e station may be called up,while when the receiver is removed and the bar has assumed its lowerposition the pin will make contact with the'spring h, closing thetalking-circuit, as will be explained later. When through talking, thereceiver is replaced into the bracket, 4whereby hook and bar are raised,the latter striking the latch and Jforcing the same up until the coneofthe push-button is free to pass through the opening therein, returningto its normal position in the space provided in the supporting-plate d,as is shownin Fig. 2. The movements ofthe switching device are shown insection in Fig. 2 and detailed in iront elevation in Figs. 3, 6, 7, 8,and 9. Fig. 6 shows the switching device in its normal position. Fig. 7shows the cone ofthe button having already passed through the opening inthe latch, this latter being again in its normal position restingagainst the stop i3. After releasing the finger from the push-button thetop rear part of the cone will rest against the top part of the latchabove its opening. Now the receiver is taken oii the bracket. The hookand bar are pressed down by means of the spring o4 acting on the bar.The bar is shown in Fig. 7 in a position half-way between its extremeupper and extreme lower position. A slight downward motion of the barwill bring its cam into touch Wi th the cam of the latch, and a stillfurther downward motion-will force the cam oi the bar to slide along thecam of the latch until both cams free each other, so

that the bar can assume its lower position. Since the pull of the springo4 in a downward vdirection is greater than in sidewise direction, thecam oi the bar will easily overcome the friction presented to it by theangle of the latch-cam, while the slight pull sidewise will bring thebar against the stop-pin o the moment the former has assumed either oneof its extreme end positions. As soon as the bar has assumed its lowerposition, as shown in Fig. 8, the pin rests against the contactspring hand establishes connection with the talking-circuit. When throughtalking, the

receiver is inserted into the bracket, whereby Y the hook p4 and with itthe bar o are moved up. Fig. 9 shows the position when the cam of thebarhas engaged the cam on the latch and has raised the latter iar enoughthat the center of the conical opening and cone coincide, thus allowingthe cone to pass this opening. The switch-spring 71 forces now thepush-button back, leaving the cone behind the latch in the spaceprovided therefor in the supporting-plate, as shown in Fig. 2. While thelatch is being pushed up by the cam of the bar, the cams move relativelyaway from each other. Subseqliliently a position will be reached wherebot cams are able to pass each other and the spring on the latch willpress this latter down against the stop, while the bar will again assumeits normal and iinal upper position, as shown in Fig. 6. Thisarrangement oi' the switching device makes it possible to call upanother station, no matter whether the receiver is in its place or not,since the push-button is released only when the bar is pushed up and notaffected when the bar moves in a downward direction.

On the fiber disk are further mounted four binding-posts r, s, t, and u,which also receive wires from the cable. One of them is the positivewire of the ringing or calling battery, one the positive wire of thetalking battery, one is the common return or negative for both, whilethe fourth wire on the bindingpost is connected to the wire representingits own instrument. These binding-posts extend up to thesupporting-plate d. They are circularly arranged, as shown in Figs. 2and 4, and somewhat shorter than the contactdowels. Four contact-clipsr, s', t', and u', one for each of these binding-posts, are secured uponthe supporting-plate. These clips have a U-shaped extension, and theouter member of the U-shaped part is in contact with the free end of oneof the bindingposts. These four clips are interconnected with thedifferent elements mounted within the frame, as contact-springs, thereceiver, transmitter, and impedance-coil. This arrangement againdispenses with flexible wires or intermediate cables.

The desk-telephone (illustrated in Fig. 10) is constructed along thesame line as the walltelephone and embodies all of the described novelfeatures. The dowels are again mounted on a plate forming the base of acasing, Jfrom the periphery of which issues a metal tube v, whichcarries the transmitter and receiver, as shown in Fig. l0. The casingcontains again the station-indicator and switching device, while thetransmitter and receiver are mounted at the top of a tubular extension oof the tube fu. The clamping device ior the receiver is similar to theone used IOO IIO

in the wall-telephone, except that the hook and passing over an idler fcdown to the bellcrank fy, mounted within the casing. Thus the movementof the hook is imparted to the the flexible band and to the bell-crank,which Will shift the bar of the switching device, as required andexplained above. Two setsA of batteries are used in connection with thissystem, one battery for calling and one Jfor talking purposes. Bothbatteries are joined with, say, their negative terminals to a commonreturn-wire, whereas the two other terminals of like polarity areconnected to two different Wires. The diiierent connections are showndiagrammatically in Figs. 12 and 13. Fig. 12 shows an arrangement wherean ordinary gong or bell is used for calling up. In Fig. 13 is shown anarrangement where the receiver of the instrument is used for the purposeof calling up. In this case calling is effected by closing a circuitcomprising the call-battery, a buzzer, and a receiver. The buzzer may beadjusted so as to give a high rate of interruptions. Then the receiverwill give a loud and clear whistling noise, loud enough for ordinarycalling purposes.

Referring to Figs. 12 and 13, the pushbutton with cone is represented by1, the switch-spring by 2, the dowels by 8, the three springs by 4, 5,and 6, the bar by 7, which at the same time acts as switch-hook. Thereis also shown an impedance-coil in the circuit. In Fig, 12 two stationsare represented, one having already called and removed the lreceiverfrom its support. Calling is eiiected by pressing the push-button untilthe cone strikes the spring 4 in the diagram. Thus a complete closedcircuit is established from the positive call-battery, over thepush-button through the switch-spring, through line 9 to the home wire10 of the called station through the bell 1 1, through the switch-hook12, through impedance-coil 13 and back through common return 14. It willbe noticed that the receiver is shunted across the bell; but owing tothe low resistance of the latter in comparison with the high resistanceof the former an insigniiicant amount of current will flow through thereceiver without affecting the bell-current. The push-button of thecalling-station is shown locked behind the latch, and the switch-hook,which represents the bar o with pin o3, closes in its upper position thelocal circuit. The current passes from the positive of thetalking-battery 15 to transmitter 16, spring-hook 7, impedance-coil 18back to common return 14. This local circuit constitutes one branch ofthe Wheatstone bridge method employed in this system. The removal of thereceiver from the hook at the called-up station closes likewise itsownlocal talking-circuit. The two stations are then connected from twopoints midway between their transmitter and impedance coils,respectively, the line including both receivers and going, as eX-`'plained, through the push-button, switchspring, and dowel of thecalling-station. In

` Fig. 13 an arrangement is shown whereby the call is aiiected throughthe receiver, like in the former arrangement, by pressing thepush-button 1 until it strikes spring 4. The calling-circuit,lcomprising battery 19, buzzer 20, and receiver 21 of called station, isclosed. The receiver of the called-up station will then whistle asintended. The removal of both receivers Jfrom their support y will, likein the preceding arrangement, close the local talking-circuit of eachstation, and the push-button of the calling-station being locked againstthe latch will again complete the connection of the two points midwaybetween transmitters and impedance-coils of each station, thisconnection comprising the two respective receivers.

Having thus described my invention, I claim as new and desire to secureby Letters Patentd 1. In an intercommunicating telephone astation-indicator comprising a name plate or dial displaying openly thevarious stations, a pointer above said dial for selecting the stations,one push-button for all the stations passing through said dial andthrough said pointer, said pointer being so arranged as to be laterallyactuated when the push-button is turned and remaining stationary whenthe push-button is depressed.

2. In an intercommunicating telephone a dial-switch comprising amultiple of circularly-arranged combined binding-posts andcontact-dowels adapted to receive directly the single wires of thehouse-cable, one pushbutton for all the contact-dowels and a curvedswitch-spring attached to the push-button and having an elongatedpointed contact portion resting always and at any time on the head ofone of the contact-dowels independent of any other electric connectionand adapted to be laterallyturned and downwardly depressed by saidpush-button whereby perfect contact is made with the desired station.

3. In an intercommunicating telephone a dial-switch comprising a nameplate or dial, a pointer in Jfront of the dial, one push-button for allthe stations passing through said dial and through said pointer, saidpointer being so arranged as to be laterally actuated by saidpush-button, a multiple of combined binding-posts and contact-dowelscircularly arranged and adapted to receive directly the single wires ofthe house-cable, and a curved switch-spring attached to the push-buttonwith an elongated contact-point which rests always and at any time onthe head of one of the contact-dowels, independent of any other electricconnection and adapted to be laterally turned and downwardly depressedby said push-button arranged so that upon turning the push-buttonlaterally the pointer and IOO ITO

contact-sprin are moved simultaneously whereby the esired station isindicated and contact made therewith.

4. In an intercommunicating telephone a push-button for all stations, astation-indicator attached to and operated by the pushbutton, a curvedswitch-spring attached to and operated by said button, a contactspringopposite the front end of same so arranged that by pushing in thebuttonl contact is made by the inner end of the button with thecontact-spring and thereby with the callcircuit and upon release thecurved spring forces back the button interrupting thereby thecall-circuit. I

5. In an intercommunicating telephone a dial-switch comprising apush-button for all the stations, a station-indicator loosely attachedto the button and operated thereby, combined binding-posts andcontact-dowels circularly arranged, a curved switch-spring attached toand operated by the push-buttonl and making contact with onecontact-dowel at a time and thereby with a station, a cone with narrowelongation in the front part of said button, a contact-spring oppositethe front end of the push-button so arranged that by pushing in thebutton its front end strikes the contact-spring in front of sameestablishing thereby connection with the call-circuit and upon releasethe button is forced back by the curved contact-spring interruptingthereby the call-circuit.

6, In an intercommunicating telephone a push-button for all stations, acurved switchspring attached to its stem near the center, a cone formedon the stem near its front end, a contact-spring directly opposite saidfront end and a contact latch or plate with opening mounted between thecone of the button and the contact-spring in front of same so that uponpushing in the button the cone passes the opening in said latch and itsfront end establishes contact with the contactspring and call-circuitand upon release the button is forced back by the force of the curvedswitch-spring interrupting the callcircuit and resting said cone againstthe contact-latch, and means connected to said latch whereby contact isestablished with the talking-circuit.

7. In an intercommunicating telephone a push-button for all stations, astation-indical tor, a curved switch-spring attached to its stem nearthe center, a cone formed on the stem near its front end, acontact-spring di- -rectly opposite said front end and a contact latchor plate with an opening mounted between the cone of the button and thecontactspring in front of same so that upon pushing in the button thecone passes through the opening in said latch and its front endestablishes contact with the contact-spring and call-circuit and uponrelease the button is t: 6 5 forced back by the force of the curvedswitchvspring interrupting the call-circuit and resting said coneagainst the contact-latch, and means connected to said latch wherebycontact is established with the talking-circuit.

8. In an intercommunicating telephone a push-button for all stations, astation-indicator, a multiple of combined binding-posts andcontact-dowels circularly arranged, a curved switch-spring attached tothe stem of the button near the center making contact with one of thedowels at a time and thereby with a station, a cone formed on the stemnear its front end, a contact-spring directly opposite said front endand a contact latch or plate with an opening mounted between the cone ofthe button and the contact-spring in front of same so that upon pushingin the button the cone passes through the opening in said latch and itsfront end establishes contact with the contact-spring and call-circuitand upon release the button is forced back by the force of the curvedswitch-spring interrupting the call-circuit and resting said coneagainst the contact-latch, and means connected to said latch wherebycontact is established with the talking-circuit,

9. In an intercommunicating telephone a dial-switch comprising apush-button for all stations, a dial, a pointer loosely attached to andoperated by said button, combined binding-posts and contact-dowelscircularly arranged acting as a multiple plug and adapted to receive thewires of the house-cable thus dispensing with the intermediate cables, acurved switch-spring secured to and actuated by the push-button, a coneformed on its stem near the inner end, a contact-spring directlyopposite said front end, and a contact latch or plate with an openingpivotally mounted between the cone of the button and the contact-springso that normally its opening is somewhat lower than the cone, and meanson the latch for connecting with the talking-circuit so that uponturning the button the pointer and dial-switch are simultaneously set onthe desired station and upon pushing in the button the switch-spring isdepressed making perfect contact with said dowel and upon furtherpushing in the inner end of the button strikes the contact-spring andconnects with the call-circuit and upon release the curved sprin Tforces back thebutton interrupting the call-circuit, and resting thecone against the latch wherebyy connection is established with thetalking-circuit.

4 l0. In an intercommunicating telephone a push-button with a cone nearits inner end, three contact-springs mounted opposite said button, acontact-latch with an opening piv- "otally mounted between said springsand the cone so that normally its opening is somewhat lower than thecone, a movable bar pivotally mounted below the latch engaging saidlatch, a contact-pin on said bar normally in contact with the outercontact or IOO IIO

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callfspring so arranged that upon pushing in the button the latch isslightly raised, then l contact is established with the inner spring andcall-circuit, and upon release the cone rests against the latch, andmeans in connection with said bar for operating same whereby thepinmakes contact with the second outer spring forming part of thetalking-circuit.

11. In an intercommunicating telephone a dial-switch consisting ofapush-button with a cone near its inner end, a station-indicator and aswitch-spring both attached to and operated by said button,circularly-arranged combined binding-posts and contact-dowels acting asa multiple plug in connection with the dial-switch, threecontact-springs mounted opposite the push-button of which one outerspring is in constant contact with the call-circuit while the inner andshorter one closes the call-circuit when the push-button strikes it andthe second outer one establishes contact with the talking-circuit, andmeans for establishing connection with said second outer spring andthereby with the talking-circuit.

12. In an intercommunicating telephone a push-button-operatedstation-indicator and switching device, a transmitter, and a receiver,three contact-springs mounted opposite the inner end of the push-button,a switchmovement mounted between said contact-springs and thepush-button consisting of a pivotally-mounted contact-latch, a movablebar pivotally mounted below the latch and engaging same, a contact-pinon said bar in contact with one outer contactspring when the telephoneis not used, a clamping device on the transmitter for supporting thereceiver having a rigid bracket below and a cap above attached to apivotally-mounted lever which is normally in contact with the lower endofthe movable bar so that upon taking oil the receiver the bar is moveddown whereby the contact-pin connects with the talking-circuit and uponinserting the receiver the bar is moved A up whereby the talking-circuitis interrupted and the outer spring of the call-circuit again in contactwith the pin of the bar.

13. In an intercommunicating telephone a push-button-operatedstation-indicator and switching device forming a self-contained part ofthe instrument and a transmitter and receiver electrically independentof the other so that each of these two parts is interchangeable as awhole. y

14. In an intercommunicating telephone a push-button-operatedstation-indicator and switching device, a multiple plug consisting ofcombined binding-posts and contact-dowels circularly arranged andsecured to a :fiber disk, and a house-cable connected to saidbinding-posts, all forming one self-contained part of the instrument,and a transmitter and l receiver electrically independent ofthe other sothat each part is interchangeable as a whole.

15. In an intercommunicating telephone a push-button-operatedstation-indicator and switching device, a multiple plug consisting ofcombined binding-posts and contact-dowels circularly arranged andsecured toa fiber binding-posts, all yforming Aone self-contained partof the instrument, a transmitter with movable hook and a receivernormally in iront of the transmitter forming a second self-containedpart, each self-contained part being interchangeable as a whole.

16. In an intercommunicating telephone a push-button-operatedstation-indicator and switching device, a multiple plug consisting ofcombined binding-posts and contact-dowels circularly arranged andsecured to a ber disk, four connecting binding-posts on said fiber diskcircularly arranged within the multiple plug, and a house-cable havingits single wires connected to the binding-posts all forming oneself-contained part, and a transmitter with clamping device and movablehook connected to the upper part of the clamping device, and a receivernormally inserted in said clamping device, all `forming a secondselfcontained part, each being interchangeable as a whole.

17. In an intercommunicating telephone a push-button-operatedstation-indicator and dial-switch, a multiple plug consisting ofcombined binding-posts and contact-dowels circularly arranged andsecured. to a fiber disk on a base-plate, three contact-springs oppositethe push-button, a switch-movement mounted between said springs and thepushbutton, a transmitter and a receiver normally on said transmitter,and means for operating said switch-movement by the removal andinsertion of said receiver.

18. In an intercommunicating telephone a push-button with a cone nearits front end, a station-indicator and dial-switch simultaneouslyoperated by said button, a multiple plug in connection with said switch,three contact-springs mounted opposite the pushbutton and aswitch-movement comprising a movable contact-latch with a cam, stop-pinand spring, a movable bar with a cam, contact pin and spring adapted toengage said latch, a transmitter and receiver, a clamping device for thelatter on said transmitter having a movable top part with hook pivotallysecured to the transmitter-frame and adapted to keep the bar of theswitch-movement in its normal position so arranged that the contact-pinon the bar rests against the outer contact-spring so that one may becalled up and by pushing in the button contact is made with the inneryspring whereby another party is called up and upon release of thereceiver from the transmitter the bar is pulled down disk, and ahouse-cable connected to said IOO the button when said cone rests theother outer contact-spring against the contact-latch of the movement.

19. ln an interoommunioating telephone a push-button-operatedstation-indicator and dial-switch, a multiple plug consisting ofcombinecl binding-posts and oontaet-dowels7 a switch-movementcontrolling the eleetrie eir- .euits, aY transmitt said transmitter,

er, a receiver normally on and means for operating said switeh-movementby the insertion of said receiver into the transmitter and the ren;

moval of same therefrom.

Signed at New of August, 1905.

York, N. Y., this 25th day LAMBERT SCHMIDT.

Witnesses z FRITZ F. P. MAURBENDEL, DANL. A. SLATTERY.

